I've come to realize that if people thumbs down you it's either because they wish they could have thought of it first and are jealous, or it's because they're pissed you thought of it first. Only two options.

The only reason the key is MIA is clearly because kinky sex went south. Said partner took key and peaced out. I'm not sure how that would work, but it's clearly the only way a key is not in this persons possession.